Once positioned in space, the Hubble Space Telescope will capture light from sources twenty times fainter compared to those that can be detected by ground-based instruments.
(A) compared to those that can be detected
(B) compared to those they can detect
(C) than that can be detected
(D) than those that can be detected（D）
(E) than those detecting
答案是D,没有问题. 我想问 : D中的that是指代those吧, 那把(D)中的that省略 改成 than those can be detected对吗? | 
